Luggage case

ABSTRACT

A luggage case includes a box-shaped frame formed of integrally molded polymeric material, and a retractable handle unit. The box-shaped frame includes a bottom portion having a plurality of openings and a surrounding wall portion upward extended from the bottom portion, and all edges of the box-shaped frame between the bottom portion and the surrounding wall portion are rounded edges. At least one of the rounded edges is provided with a recessed rib portion having two insertion holes provided thereon. The retractable handle unit includes two retractable bars that are inserted into the two insertion holes with two upper ends located outside the box-shaped frame to connect to a transverse grip portion, and two lower ends extended into a holding block located inside and connected to the box-shaped frame. Being supported by the box-shaped frame and the retractable handle unit, the luggage case has reduced weight but good structural strength.

FIELD OF THE INVENTION

The present invention relates to a luggage case, and more particularly to a luggage case that has an integrally molded inner supporting frame and therefore has increased structural strength but reduced weight.

BACKGROUND OF THE INVENTION

A traveler often uses a luggage case to conveniently hold personal items and clothes therein. To protect the luggage case against damage during travel, most of the currently available luggage cases are so designed that they have fixed shape and structural strength sufficient to resist forces externally applied thereto. The currently available luggage cases are also internally provided with binding straps or other holding means for holding personal items and clothes in place in the luggage cases.

FIG. 1 is an exploded perspective view of a conventional luggage case, which includes an inner frame 90 and an outer enclosure 91. The inner frame 90 includes an upper shell 92, a lower shell 93, and supporting rods 94 connected to between the upper and lower shells 92, 93. The outer enclosure 91 can be a cover made of thick cloth or injection-molded foam material, and is riveted or bonded to an outer side of the inner frame 90, so that the inner frame 90 supports the outer enclosure 91 to constitute a strong luggage case.

A strong luggage case having a large capacity usually has increased gross weight as high as 3 to 5 kg. An excessively heavy luggage case not only increases the user's burden in handling or moving it, but also reduces the quantity of things that can be held therein because all airlines place limit on the weight of luggage one can carry on to a flight with him.

SUMMARY OF THE INVENTION

It is therefore a primary object of the present invention to provide a luggage case that has an inner supporting frame capable of reducing the weight of the luggage case without scarifying the structural strength thereof.

To achieve the above and other objects, the luggage case according to an embodiment of the present invention includes a box-shaped frame, a retractable handle unit, an exterior cover, and a lid. The box-shaped frame is an open-topped box being integrally molded from a polymeric material, and having a bottom portion and a surrounding wall portion upward extended from a periphery of the bottom portion. All edges of the box-shaped frame between the bottom portion and the surrounding wall portion are rounded edges, and at least one of the rounded edges is provided with a recessed rib portion that is sunken from the surrounding wall portion into the box-shaped frame. A pair of insertion holes is provided on one side of the recessed rib portion perpendicular to the bottom portion, and the bottom portion is formed with a plurality of openings. The retractable handle unit includes two retractable bars, a grip portion and a holding block. The retractable bars are inserted into the two insertion holes on the recessed rib portion with two upper ends of the retractable bars located outside the box-shaped frame. The grip portion is transversely extended between the upper ends of the two retractable bars. The holding block is located inside and connected to the box-shaped frame with lower ends of the two retractable bars extended thereinto. The exterior cover is fixedly covered onto an exterior of the box-shaped frame. The lid is hinged to an open top of the box-shaped frame, and is provided with a fastening device, via which the lid is connected to the box-shaped frame to close the open top thereof.

In a preferred embodiment, the box-shaped frame is formed at bottom corners with a recession each. The recession includes a curved surface portion and inward bent wall portions located around the curved surface portion. The inward bent wall portions is formed by inward bending an outer surface of the box-shaped frame at the bottom corner by a predetermined depth; and the curved surface portion is perpendicular to a direction in which an external force is applied thereto.

In another preferred embodiment, the luggage case further includes corner protective caps for covering the recessions on the box-shaped frame. The corner protective caps respectively include three planar portions perpendicular to one another, and the planar portions are so connected to one another that the corner protective caps respectively have an outward smoothly curved shape for fitly attaching to the recessions. Further, the planar portions are respectively provided with a rivet hole, so that the corner protective caps are riveted to the box-shaped frame via the rivet holes.

In another embodiment of the present invention, the luggage case further includes two wheel assemblies connected to two of the recessions; and each of the wheel assemblies includes a wheel holder riveted to the recession and a wheel rotatably connected to the wheel holder.

In an embodiment of the present invention, the retractable handle unit further includes a reinforcing plate being configured corresponding to the recessed rib portion for fitly attached to an outer side of the recessed rib portion. The reinforcing plate is provided with two through holes corresponding to the two insertion holes on the recessed rib portion for the two retractable bars to extend therethrough.

The luggage case of the present invention is characterized in that the holding block and the recessed rib portion along with the two retractable bars extended therethrough and accordingly connected thereto together support and maintain the box-shaped frame in its designed shape; and that the surrounding wall portion of the box-shaped frame provides a supporting force that is needed to protect the whole luggage case against deformation due to forces externally applied thereto. Compared to the conventional luggage case structure, the luggage case according to the present invention includes only one single simplified box-shaped frame, which has largely reduced weight and is provided at one side with a recessed rib portion and at bottom corners with recessions to thereby possess increased structural strength for resisting external force applied thereto. With the simplified box-shaped frame, the luggage case of the present invention can also be more easily assembled to reduce manufacturing cost thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein

FIG. 1 is an exploded perspective view of a conventional luggage case structure;

FIG. 2 is an exploded perspective view of a luggage case according to an embodiment of the present invention;

FIG. 3 is an enlarged top view showing two recessions formed at a pair of first bottom corners of the luggage case of the present invention;

FIG. 4 is a fragmentary top perspective view showing the luggage case of the present invention includes a corner protective cap for each of the recessions of FIG. 3;

FIG. 5 is a fragmentary bottom perspective view showing the luggage case of the present invention includes two wheels assembled to a pair of second bottom corners thereof; and

FIG. 6 is a fragmentary exploded perspective view showing a reinforcing plate for the luggage case of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described with some preferred embodiments thereof and with reference to the accompanying drawings.

Please refer to FIG. 2 that is an exploded perspective view of a luggage case according to an embodiment of the present invention. As shown, the luggage case includes a box-shaped frame 10, a retractable handle unit 20, an exterior cover 30, and a lid 40. The box-shaped frame 10 is an open-topped box integrally molded from a polymeric material, and includes a bottom portion 11 and a surrounding wall portion 12 upward extended from a periphery of the bottom portion 11. All edges of the box-shaped frame 10 between the bottom portion 11 and the surrounding wall portion 12 are rounded edges 13. At least one of the rounded edges 13 is provided with a recessed rib portion 16 that is sunken from the surrounding wall portion 12 into the box-shaped frame 10.

A pair of insertion holes 14 is provided on one side of the recessed rib portion 16 perpendicular to the bottom portion 11. For the luggage case of the present invention to have further reduced weight, the bottom portion 11 is formed with a plurality of openings 15. The retractable handle unit 20 includes two retractable bars 21, a grip portion 22, and a holding block 23. The two retractable bars 21 are extended through the two insertion holes 14 into the box-shaped frame 10 with upper ends of the two retractable bars 21 located outside the box-shaped frame 10. The grip portion 22 is transversely extended between the upper ends of the two retractable bars 21.

The holding block 23 is provided inside and connected to the box-shaped frame 10 to locate in parallel with the recessed rib portion 16. The two retractable bars 21 are extended through the insertion holes 14 with lower ends extended into the holding block 23. The exterior cover 30 is fixedly covered onto an exterior of the box-shaped frame 10. The lid 40 is hinged to the box-shaped frame 10 for openably closing an open top of the box-shaped frame 10. The lid 40 is provided with a fastening device 41, via which the lid 40 is connected to the box-shaped frame 10 and closes the open top thereof. In the illustrated embodiment, the fastening device 41 can be a zipper without being limited thereto.

The recessed rib portion 16, the holding block 23, and the two retractable bars 21 connected to the recessed rib portion 16 and the holding block 23 together form a rectangular frame structure in the box-shaped frame 10. This rectangular frame structure is able to support and maintain the box-shaped frame 10 in its designed shape. In addition, the surrounding wall portion 12 also provides a supporting force that is needed to protect the whole luggage case against deformation and forces externally applied thereto.

Please refer to FIG. 3. The box-shaped frame 10 has bottom corners 17 that are most easily subjected to external impact when compared to other areas of the luggage case. To provide the luggage case of the present invention with further increased impact resistance, the bottom corners 17 are respectively provided with a recession 18. The recession 18 includes a curved surface portion 182 and inward bent wall portions 181 located around the curved surface portion 182. With the inward bent wall portions 181 of the recessions 18, the bottom corners 17 of the box-shaped frame 10 can have increased strength to resist external force applied thereto. To avoid the recessions 18 from reducing too many inner space of the luggage case and to increase the force bearing areas at the bottom corners 17, the inward bent wall portions 181 are formed by inward bending an outer surface of the box-shaped frame 10 at the bottom corners by a predetermined depth in parallel to a direction in which an external force is applied to the bottom corners 17, and the curved surface portion 182 is substantially perpendicular to the force applying direction. In the present invention, the recessions 18 can be differently configured according to different purposes thereof.

Please refer to FIG. 4 that is a fragmentary perspective view of the illustrated embodiment of the present invention showing the recessions 18 formed at a pair of first bottom corners 17 closer to the recessed rib portion 16 of the box-shaped frame 10 for resisting external impact applied to the first bottom corners 17. The first bottom corners 17 are located at upper positions when the luggage case is moved by a user via the retractable handle unit (not shown in FIG. 4), and are therefore easily subjected to deformation due to external forces downwardly or obliquely applied thereto. The inward bent wall portions 181 of the recessions 18 having a predetermined depth give the first bottom corners 17 with enhanced impact strength, and the curved surface portions 182 of the recessions 18 provide increased areas, over which the impact force can be advantageously distributed.

To further increase the impact strength of the luggage case at the first bottom corners 17, two corner protective caps 50 are provided for covering the recessions 18 at the first bottom corners 17. The corner protective caps 50 respectively include three planar portions 51 perpendicular to one another. The planar portions 51 are so connected to one another that the corner protective caps 50 respectively have an outward smoothly curved shape for fitly attaching to the recessions 18. The planar portions 51 are respectively provided with a rivet hole 52, so that the corner protective caps 50 can be riveted to the box-shaped frame 10 via the rivet holes 52.

In the case the corner protective caps 50 are subjected to an external impact, the outward smoothly curved shape of the corner protective caps 50 would advantageously distribute the external impact over rivets extended through the three rivet holes 52, protecting the luggage case against damage due to concentrated stress.

Please refer to FIG. 5. In another embodiment of the present invention, two recessions 18 are formed at a pair of second bottom corners 17 of the box-shaped frame 10 opposite to the recessed rib portion 16 and the first bottom corners 17, so as to give the box-shaped frame 10 with increased impact strength at the second bottom corners 17. Meanwhile, two wheel assemblies 60 are separately connected to the recessions 18 at the second bottom corners 17. The wheel assemblies 60 respectively include a wheel holder 61 riveted to the recession 18 and a wheel 62 rotatably connected to the wheel holder 61. In the illustrated another embodiment, the wheel assemblies 60 will alone bear the largest pressure when the luggage case is placed on a ground in an upright position. With the upright position, force applied to the luggage case is perpendicular to the ground. To support and protect the luggage case against deformation possibly caused by the pressure perpendicular to the ground, the recessions 18 formed at the second bottom corners 17 respectively have a curved surface portion 182 substantially parallel to the ground.

It is understood the recessions 18 in the above embodiments are only illustrative and not intended to limit the shapes of the inward bent wall portions 181 and the curved surface portions 182 in any way. That is, the direction in which a luggage case is subjected to pressure varies with the design and shape of the luggage case. Therefore, the shapes of the inward bent wall portions 181 and of the curved surface portions 182 for the recessions 18 at the first and second bottom corners 17 of the box-shaped frame 10 should also be adjusted according to the exact direction in which pressure is applied to the luggage case at the bottom corners 17.

Please refer to FIG. 6. To avoid the recessed rib portion 16 from deformation due to an impact directly applied thereto, the retractable handle unit 20 according to a further embodiment of the present invention includes a reinforcing plate 24 for connecting to an outer side of the recessed rib portion 16. The reinforcing plate 24 is configured corresponding to the recessed rib portion 16 for fitly bearing on the latter, so as to uniformly distribute any external impact over the whole recessed rib portion 16. The reinforcing plate 24 is provided with two through holes 25 corresponding to the two insertion holes 14 for the two retractable bars 21 of the retractable handle unit 20 to extend therethrough.

In brief, the holding block 23 and the recessed rib portion 16 along with the two retractable bars 21 extended therethrough and accordingly connected thereto together support and maintain the box-shaped frame 10 in its designed shape; and the surrounding wall portion 12 of the box-shaped frame 10 provides a supporting force that is needed to protect the whole luggage case against deformation and forces externally applied thereto. Compared to the conventional luggage case structure, the luggage case according to the present invention includes only one single simplified box-shaped frame, which has largely reduced weight and is provided at one side with a recessed rib portion and at four bottom corners with recessions to thereby possess increased structural strength for resisting externally applied force.

With the simplified box-shaped frame, the luggage case of the present invention can also be more easily assembled to reduce manufacturing cost thereof.

The present invention has been described with some preferred embodiments thereof and it is understood that many changes and modifications in the described embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims. 

1. A luggage case, comprising: a box-shaped frame being an open-topped box integrally molded from a polymeric material, and having a bottom portion and a surrounding wall portion upward extended from a periphery of the bottom portion; all edges of the box-shaped frame between the bottom portion and the surrounding wall portion being rounded edges; at least one of the rounded edges being provided with a recessed rib portion that is sunken from the surrounding wall portion into the box-shaped frame; a pair of insertion holes being provided on one side of the recessed rib portion perpendicular to the bottom portion; and the bottom portion being formed with a plurality of openings; a retractable handle unit including two retractable bars, a grip portion and a holding block; the retractable bars being inserted into the two insertion holes on the recessed rib portion with two upper ends of the retractable bars located outside the box-shaped frame, the grip portion being transversely extended between the upper ends of the two retractable bars, and the holding block being located inside and connected to the box-shaped frame with lower ends of the two retractable bars extended into and connected to the holding block; an exterior cover being fixedly covered onto an exterior of the box-shaped frame; and a lid being hinged to an open top of the box-shaped frame, and being provided with a fastening device, via which the lid is connected to the box-shaped frame to close the open top thereof.
 2. The luggage case as claimed in claim 1, wherein the box-shaped frame is formed at bottom corners with a recession each; the recession including a curved surface portion and inward bent wall portions located around the curved surface portion; the inward bent wall portions being formed by inward bending an outer surface of the box-shaped frame at the bottom corner by a predetermined depth; and the curved surface portion being perpendicular to a direction in which an external force is applied thereto.
 3. The luggage case as claimed in claim 2, further comprising corner protective caps for covering the recessions on the box-shaped frame; the corner protective caps respectively including three planar portions perpendicular to one another, and the planar portions being so connected to one another that the corner protective caps respectively have an outward smoothly curved shape for fitly attaching to the recessions.
 4. The luggage case as claimed in claim 3, wherein the planar portions are respectively provided with a rivet hole, so that the corner protective caps are riveted to the box-shaped frame via the rivet holes.
 5. The luggage case as claimed in claim 2, further comprising two wheel assemblies connected to two of the recessions; and each of the wheel assemblies including a wheel holder riveted to the recession and a wheel rotatably connected to the wheel holder.
 6. The luggage case as claimed in claim 1, wherein the retractable handle unit further includes a reinforcing plate being configured corresponding to the recessed rib portion for fitly connecting to an outer side of the recessed rib portion; and the reinforcing plate being provided with two through holes corresponding to the two insertion holes on the recessed rib portion for the two retractable bars of the retractable handle unit to extend therethrough. 